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The carrot (Daucus carota subsp. sativus) is a root vegetable, typically orange in colour, though heirloom variants including purple, black, red, white, and yellow cultivars exist, all of which are domesticated forms of the wild carrot, Daucus carota, native to Europe and Southwestern Asia. The plant probably originated in Iran and was originally cultivated for its leaves and seeds.

The carrot is a biennial plant in the umbellifer family, Apiaceae. World production of carrots (combined with turnips) for 2022 was 42 million tonnes, led by China producing 44% of the total.

The characteristic orange colour is from beta-carotene, making carrots a rich source of vitamin A. A myth that carrots help people to see in the dark was spread as propaganda in the Second World War, to account for the ability of British pilots to fight in the dark; the real explanation was the introduction of radar.

Etymology

The word is first recorded in English around 1530 and was borrowed from the Middle French carotte, itself from the Late Latin carōta, from the ancient Greek καρωτόν (karōtón), originally from the Proto-Indo-European root *ker- (‘horn’), due to its horn-like shape.^[3] In Old English, carrots (typically white at the time) were not clearly distinguished from parsnips.^[3] The word’s use as a colour name in English was first recorded around 1670, originally referring to yellowish-red hair.^[3]

Description

Daucus carota is a biennial plant. In the first year, energy is stored in the taproot to enable the plant to flower in its second year.^[4]

Soon after germination, carrot seedlings show a distinct demarcation between taproot and stem: the stem is thicker and lacks lateral roots. At the upper end of the stem is the seed leaf. The first true leaf appears about 10–15 days after germination. Subsequent leaves are alternate (with a single leaf attached to a node), spirally arranged, and pinnately compound, with leaf bases sheathing the stem. As the plant grows, the bases of the seed leaves, near the taproot, are pushed apart. The stem, located just above the ground, is compressed and the internodes are not distinct. When the seed stalk elongates for flowering, the tip of the stem narrows and becomes pointed, and the stem extends upward to become a highly branched inflorescence up to 60–200 cm (20–80 in) tall.^[5]

Most of the taproot consists of a pulpy outer cortex (phloem) and an inner core (xylem). High-quality carrots have a large proportion of cortex compared to core. Although a completely xylem-free carrot is not possible, some cultivars have small and deeply pigmented cores; the taproot can appear to lack a core when the colour of the cortex and core are similar in intensity. Taproots are typically long and conical, although cylindrical and nearly spherical cultivars are available. The root diameter can range from 1 cm (³⁄₈ in) to as much as 10 cm (4 in) at the widest part. The root length ranges from 5 to 50 cm (2 to 20 in), although most are between 10 and 25 cm (4 and 10 in).^[5]

Flower development begins when the flat meristem changes from producing leaves to an uplifted, conical meristem capable of producing stem elongation and a cluster of flowers. The cluster is a compound umbel, and each umbel contains several smaller umbels (umbellets). The first (primary) umbel occurs at the end of the main floral stem; smaller secondary umbels grow from the main branch, and these further branch into third, fourth, and even later-flowering umbels.^[5]

A large, primary umbel can contain up to 50 umbellets, each of which may have as many as 50 flowers; subsequent umbels have fewer flowers. Individual flowers are small and white, sometimes with a light green or yellow tint. They consist of five petals, five stamens, and an entire calyx. The stamens usually split and fall off before the stigma becomes receptive to receive pollen. The stamens of the brown, male, sterile flowers degenerate and shrivel before the flower fully opens. In the other type of male sterile flower, the stamens are replaced by petals, and these petals do not fall off. A nectar-containing disc is present on the upper surface of the carpels.^[5]

Flowers change sex in their development, so the stamens release their pollen before the stigma of the same flower is receptive. The arrangement is centripetal, meaning the oldest flowers are near the edge and the youngest flowers are in the center. Flowers usually first open at the outer edge of the primary umbel, followed about a week later on the secondary umbels, and then in subsequent weeks in higher-order umbels.^[5]

The usual flowering period of individual umbels is 7 to 10 days, so a plant can be in the process of flowering for 30–50 days. The distinctive umbels and floral nectaries attract pollinating insects. After fertilization and as seeds develop, the outer umbellets of an umbel bend inward causing the umbel shape to change from slightly convex or fairly flat to concave, and when cupped it resembles a bird’s nest.^[5]

The fruit that develops is a schizocarp consisting of two mericarps; each mericarp is a true seed. The paired mericarps are easily separated when they are dry. Premature separation (shattering) before harvest is undesirable because it can result in seed loss. Mature seeds are flattened on the commissural side that faced the septum of the ovary. The flattened side has five longitudinal ribs. The bristly hairs that protrude from some ribs are usually removed by abrasion during milling and cleaning. Seeds also contain oil ducts and canals. Seeds vary somewhat in size, ranging from less than 500 to more than 1000 seeds per gram.^[5]

The carrot is a diploid species, and has nine relatively short, uniform-length chromosomes (2n=18).^[6][7] The genome size is estimated to be 473 mega base pairs, which is four times larger than Arabidopsis thaliana, one-fifth the size of the maize genome, and about the same size as the rice genome.^[8]

• Seedlings shortly after germination
• Flowers consist of five petals, five stamens, and an entire calyx.
• Daucus carota umbel (inflorescence). Individual flowers are borne on undivided pedicels from a common node.
• Top view of Daucus carota inflorescence, showing umbellets; the central flower is dark red.
• Roots at market

Chemistry

Polyacetylenes can be found in Apiaceae vegetables like carrots where they show cytotoxic activities.^[9][10] Falcarinol and falcarindiol (cis-heptadeca-1,9-diene-4,6-diyne-3,8-diol)^[11] are such compounds. This latter compound shows antifungal activity towards Mycocentrospora acerina and Cladosporium cladosporioides.^[11] Falcarindiol is the main compound responsible for bitterness in carrots.^[12]

Other compounds include pyrrolidine present in the leaves^[13] and 6-hydroxymellein.^[14]

Taxonomy

Both written history and molecular genetic studies indicate that the domestic carrot has a single origin in Central Asia.^[6][7] Its wild ancestors probably originated in Greater Iran (regions of which are now Iran and Afghanistan), which remains the centre of diversity for the wild carrot Daucus carota. A naturally occurring subspecies of the wild carrot was presumably bred selectively over the centuries to reduce bitterness, increase sweetness and minimise the woody core; this process produced the familiar garden vegetable.^[15][16]

Cultivation

History

When first cultivated, carrots were grown for their aromatic leaves and seeds rather than their roots. Carrot seeds have been found in Switzerland and Southern Germany dating back to 2000–3000 BC.^[17] Some close relatives of the carrot are still grown for their leaves and seeds, such as parsley, coriander (cilantro), fennel, anise, dill and cumin. The first mention of the root in classical sources is from the 1st century AD;^[18] the Romans ate a root vegetable called pastinaca,^[19] which may have been either the carrot or the closely related parsnip.^[20][21]

The plant is depicted and described in the Eastern Roman Juliana Anicia Codex, a 6th-century AD Constantinopolitan copy of the Greek physician Dioscorides‘ 1st-century pharmacopoeia of herbs and medicines, De Materia Medica. The text states that “the root can be cooked and eaten”.^[22] Another copy of this work, Codex Neapolitanes from the late 6th or early 7th century, has basically the same illustrations but with roots in purple.^[23]

The plant was introduced into Spain by the Moors in the 8th century.^[24] In the 10th century, roots from West Asia, India and Europe were purple.^[25] The modern carrot originated in Afghanistan at about this time.^[18] The 11th-century Jewish scholar Simeon Seth describes both red and yellow carrots,^[26] as does the 12th-century Arab-Andalusian agriculturist, Ibn al-‘Awwam.^[27] Cultivated carrots appeared in China in the 12th century,^[28] and in Japan in the 16th or 17th century.^[29]

The orange carrot was created by Dutch growers. There is pictorial evidence that the orange carrot existed at least in 512 AD, but it is probable that it was not a stable variety until the Dutch bred the cultivar termed the “Long Orange” at the start of the 18th century.^[30] Some claim that the Dutch created the orange carrots to honor the Dutch flag at the time and William of Orange,^[25][31] but other authorities argue these claims lack convincing evidence and it is possible that the orange carrot was favored by the Europeans because it does not brown the soups and stews as the purple carrot does and, as such, was more visually attractive.^[30]

Modern carrots were described at about this time by the English antiquary John Aubrey (1626–1697): “Carrots were first sown at Beckington in Somersetshire. Some very old Man there [in 1668] did remember their first bringing hither.”^[32] European settlers introduced the carrot to colonial America in the 17th century.^[33] Outwardly purple carrots, still orange on the inside, were sold in British stores beginning in 2002.^[25]

Propagation

Carrots are grown from seed and can take up to four months (120 days) to mature, but most cultivars mature within 70 to 80 days under the right conditions.^[34] They grow best in full sun but tolerate some shade.^[35] The optimum temperature is 16 to 21 °C (61 to 70 °F).^[36] The ideal soil is deep, loose and well-drained, sandy or loamy, with a pH of 6.3 to 6.8.^[37]

Fertilizer should be applied according to soil type because the crop requires low levels of nitrogen, moderate phosphate and high potash. Rich or rocky soils should be avoided, as these will cause the roots to become hairy and/or misshapen.^[38] Irrigation is applied when needed to keep the soil moist. After sprouting, the crop is eventually thinned to a spacing of 8 to 10 cm (3 to 4 in) and weeded to prevent competition beneath the soil.^[34][39]

Pests and diseases

Further information: List of carrot diseases

There are several diseases that can reduce the yield and market value of carrots. The most devastating carrot disease is Alternaria leaf blight, which has been known to eradicate entire crops. A bacterial leaf blight caused by Xanthomonas campestris can also be destructive in warm, humid areas. Root knot nematodes (Meloidogyne species) can cause stubby or forked roots, or galls.^[40] Cavity spot, caused by the oomycetes Pythium violae and Pythium sulcatum, results in irregularly shaped, depressed lesions on the taproots.^[41]

Physical damage can also reduce the value of carrot crops. The two main forms of damage are splitting, whereby a longitudinal crack develops during growth that can be a few centimetres to the entire length of the root, and breaking, which occurs postharvest. These disorders can affect over 30% of commercial crops. Factors associated with high levels of splitting include wide plant spacing, early sowing, lengthy growth durations, and genotype.^[42]

Carrots can be good companions for other plants; if left to flower, the carrot, like any umbellifer, attracts predatory wasps that kill many garden pests.^[43]

Cultivars

Carrot cultivars can be grouped into two broad classes: “Eastern” carrots and “Western” carrots.^[44] A number of novelty cultivars have been bred for particular characteristics.^[6][7]

“Eastern” (a European and American continent reference) carrots were domesticated in Persia (probably in the lands of modern-day Iran and Afghanistan within West Asia) during the 10th century, or possibly earlier. Specimens of the Eastern carrot that survive to the present day are commonly purple or yellow, and often have branched roots. The purple colour common in these carrots comes from anthocyanin pigments.^[45]

The “Western” carrot emerged in the Netherlands in the 16th or 17th century.^[46] There is a popular belief that its orange colour made it popular in those countries as an emblem of the House of Orange and the struggle for Dutch independence, although there is little evidence for this beyond oral tradition and the timing.^[30][31]

Western carrot cultivars are commonly classified by their root shape. The four general types are:

• Chantenay. Although the roots are shorter than other cultivars, they have vigorous foliage and greater girth, being broad in the shoulders and tapering towards a blunt, rounded tip. They store well, have a pale core, and are mostly used for processing.^[39]
• Danvers. These have strong foliage, and the roots are longer than Chantenay types, and they have a conical shape with a well-defined shoulder, tapering to a point. They are somewhat shorter than Imperator cultivars, but more tolerant of heavy soil conditions. Danvers cultivars store well and are used both fresh and for processing.^[39] They were developed in 1871 in Danvers, Massachusetts.^[47]
• Imperator. This cultivar has vigorous foliage, is of high sugar content, and has long and slender roots, tapering to a pointed tip. Imperator types are the most widely cultivated by commercial growers.^[39]
• Nantes. These have sparse foliage, are cylindrical, short with a blunter tip than Imperator types, and attain high yields in a range of conditions. The skin is easily damaged and the core is deeply pigmented. They are brittle, high in sugar, and store less well than other types.^[39]

Breeding programs have developed new cultivars to have dense amounts of chemically-stable acylated pigments, such as anthocyanins, which can produce different colours.^[6][7] One particular cultivar lacks the usual orange pigment due to carotene, owing its white colour to a recessive gene for tocopherol (vitamin E), but this cultivar and wild carrots do not provide nutritionally significant amounts of vitamin E.^[48]

China	18.7
Uzbekistan	3.9
United States	1.4
Russia	1.4
United Kingdom	0.9
Turkey	0.8
Germany	0.8
World	42.2
Source: FAOSTAT of the United Nations[49]

Storage

Carrots can be stored for several months in the refrigerator or over winter in a cool dry place. For long term storage, unwashed carrots can be placed in a bucket between dry layers of sand, a 50/50 mix of sand and wood shavings, or in soil. A temperature range of 0 to 4 °C (32 to 40 °F) and 90–95% humidity is best.^[50][51] During storage, carrots may be subject to the development of bitterness, white blush, and browning, leading to carrot losses.^[52] Bitterness can be prevented by storage in well-ventilated rooms with low ethylene content (for example, without ethylene-producing fruit and vegetables). White blush and browning can be countered with application of edible films, heat treatment, application of hydrogen sulfide, and ultraviolet irradiation.^[52]

Production

In 2022, world production of carrots (combined with turnips) was 42 million tonnes, led by China with 44% of the total. Uzbekistan, the United States, and Russia were the only other countries producing over 1 million tonnes annually (table).

Uses

Nutrition

Nutritional value per 100 g (3.5 oz)
Energy	173 kJ (41 kcal)
Carbohydrates	9.6 g
Sugars	4.7 g
Dietary fiber	2.8 g
Fat	0.24 g
Protein	0.93 g
showVitamins and minerals
Other constituents	Quantity
Water	88 g
Link to USDA Database Entry
†Percentages estimated using US recommendations for adults,[53] except for potassium, which is estimated based on expert recommendation from the National Academies.[54]

Raw carrots are 88% water, 9% carbohydrates, 1% protein, and contain negligible fat (table). In a reference amount of 100 grams (3.5 oz), raw carrots supply 41 calories and have a rich content (20% or more of the Daily Value, DV) of vitamin A (93% DV) and a moderate amount (10–19% DV) of vitamin K (11% DV) and potassium (11% DV), but otherwise have low content of micronutrients (table).

As a common source of beta-carotene in diets, carrots are a provitamin A source; an enzyme that converts beta-carotene into vitamin A in the small intestine.^[55][56]

Culinary

Further information: List of carrot dishes

Wikibooks Cookbook has a recipe/module on

• Carrot

Carrots can be eaten in a variety of ways. Only 3 percent of the β-carotene in raw carrots is released during digestion: this can be improved to 39% by pulping, cooking and adding cooking oil.^[57] Alternatively they may be chopped and boiled, fried or steamed, and cooked in soups and stews, as well as baby and pet foods. A well-known dish is carrots julienne.^[58] Together with onion and celery, carrots are one of the primary vegetables used in a mirepoix to make broths.^[59]

The greens are edible as a leaf vegetable,^[60][61] but are rarely eaten by humans;^[62] some sources suggest that the greens contain toxic alkaloids.^[63][64] When used for this purpose, they are harvested young in high-density plantings, before significant root development, and typically used stir-fried, or in salads.^[62] Some people are allergic to carrots. In a 2010 study on the prevalence of food allergies in Europe, 3.6 percent of young adults showed some degree of sensitivity to carrots.^[65] Because the major carrot allergen, the protein Dauc c 1.0104, is cross-reactive with homologues in birch pollen (Bet v 1) and mugwort pollen (Art v 1), most carrot allergy sufferers are also allergic to pollen from these plants.^[66]

In India, carrots are used in a variety of ways, as salads or as vegetables added to spicy rice or dal dishes. A popular variation in north India is the gajar ka halwa carrot dessert, which has carrots grated and cooked in milk until the whole mixture is solid, after which nuts and butter are added.^[67] Carrot salads are usually made with grated carrots with a seasoning of mustard seeds and green chillies popped in hot oil. Carrots can also be cut into thin strips and added to rice, can form part of a dish of mixed roast vegetables, or can be blended with tamarind to make chutney.^[68] Since the late 1980s, baby carrots or mini-carrots (carrots that have been peeled and cut into uniform cylinders) have been a popular ready-to-eat snack food available in many supermarkets.^[69] Carrot juice is widely marketed, especially as a health drink, either stand-alone or blended with juices from fruits and other vegetables.^[70]

The sweetness of carrots allows the vegetable to be used in some fruit-like roles. They are used grated in carrot cakes, as well as carrot puddings, an English dish thought to have originated in the early 19th century.^[71] Carrots can be used alone or blended with fruits in jams and preserves. In the European Union, there is a rule specifying that only fruits can be used in making jams; to preserve the Portuguese carrot jam delicacy (or Doce de Cenoura in Portuguese), the Council of the European Union adopted a directive that, for purposes of regulation of fruit jams and jellies, considers carrots as fruit.^[72]

Very high consumption of carrots over a long period of time can result in carotenemia, a harmless yellow-orange discoloration of the skin caused by a buildup of carotenoids.^[73]

In culture

Despite popular belief, the provitamin A beta-carotene from carrots does not actually help people to see in the dark unless they suffer from vitamin A deficiency.^[55] This myth was propaganda used by the Royal Air Force during the Second World War to explain why British pilots had improved night vision which enabled their success during nighttime air battles; in reality, it was thanks to newly adopted radar technology.^[74]

The consumption of carrots was advocated in Britain at the time as part of a Dig for Victory campaign. A radio program called The Kitchen Front encouraged people to grow, store and use carrots in various novel ways, including making carrot jam and Woolton pie, named after the Lord Woolton, the Minister for Food.^[75] The British public during WWII generally believed that eating carrots would help them see better at night and in 1942 there was a 100,000-ton surplus of carrots from the extra production.

The sweet potato or sweetpotato (Ipomoea batatas) is a dicotyledonous plant that belongs to the bindweed or morning glory family, Convolvulaceae. Its large, starchy, sweet-tasting tuberous roots are used as a root vegetable.^[3][4] The young shoots and leaves are sometimes eaten as greens. Cultivars of the sweet potato have been bred to bear tubers with flesh and skin of various colors. Sweet potato is only distantly related to the common potato (Solanum tuberosum), both being in the order Solanales. Although darker sweet potatoes are often referred to as “yams” in parts of North America, the species is even more distant from the true yams, which are monocots in the order Dioscoreales.^[5]

The sweet potato is native to the tropical regions of South America in what is present-day Ecuador.^[6][7] Of the approximately 50 genera and more than 1,000 species of Convolvulaceae, I. batatas is the only crop plant of major importance—some others are used locally (e.g., I. aquatica “kangkong” as a green vegetable), but many are poisonous. The genus Ipomoea that contains the sweet potato also includes several garden flowers called morning glories, but that term is not usually extended to I. batatas. Some cultivars of I. batatas are grown as ornamental plants under the name tuberous morning glory, and used in a horticultural context. Sweet potatoes can also be called yams in North America. When soft varieties were first grown commercially there, there was a need to differentiate between the two. Enslaved Africans had already been calling the ‘soft’ sweet potatoes ‘yams’ because they resembled the unrelated yams in Africa.^[8] Thus, ‘soft’ sweet potatoes were referred to as ‘yams’ to distinguish them from the ‘firm’ varieties.

Description

[edit]

The plant is a herbaceous perennial vine, bearing alternate triangle-shaped or palmately lobed leaves and medium-sized sympetalous flowers. The stems are usually crawling on the ground and form adventitious roots at the nodes. The leaves are screwed along the stems. The leaf stalk is 13 to 51 centimetres (5 to 20 inches) long. The leaf blades are very variable, 5 to 13 cm (2 to 5 in) long, the shape is heart-, kidney- to egg-shaped, rounded or triangular and spear-shaped, the edge can be entire, toothed or often three to seven times lobed, cut or divided. Most of the leaf surfaces are bare, rarely hairy, and the tip is rounded to pointed. The leaves are mostly green in color, but the accumulation of anthocyanins, especially along the leaf veins, can make them purple. Depending on the variety, the total length of a stem can be between 0.5 and 4 metres (1+¹⁄₂ and 13 feet). Some cultivars also form shoots up to 16 m (52 ft) in length. However, these do not form underground storage organs.^{[citation needed]}

The hermaphrodite, five-fold and short-stalked flowers are single or few in stalked, zymous inflorescences that arise from the leaf axils and stand upright. It produces flowers when the day is short. The small sepals are elongated and tapering to a point and spiky and (rarely only 7) 10 to 15 millimetres (³⁄₈ to ⁵⁄₈ in) long, usually finely haired or ciliate. The inner three are a little longer. The 4 to 7 cm (1+¹⁄₂ to 2+³⁄₄ in) long, overgrown and funnel-shaped, folded crown, with a shorter hem, can be lavender to purple-lavender in color, the throat is usually darker in color, but white crowns can also appear. The enclosed stamens are of unequal length with glandular filaments. The two-chamber ovary is upper constant with a relatively short stylus.^{[citation needed]} Seeds are only produced from cross-pollination.^[9]

The flowers open before sunrise and stay open for a few hours. They close again in the morning and begin to wither. The edible tuberous root is long and tapered, with a smooth skin whose color ranges between yellow, orange, red, brown, purple, and beige. Its flesh ranges from beige through white, red, pink, violet, yellow, orange, and purple. Sweet potato cultivars with white or pale yellow flesh are less sweet and moist than those with red, pink or orange flesh.^[10]

Taxonomy

[edit]

The sweet potato originates in South America in what is present-day Ecuador.^[6][7] The domestication of sweet potato occurred in either Central or South America.^[12] In Central America, domesticated sweet potatoes were present at least 5,000 years ago,^[13] with the origin of I. batatas possibly between the Yucatán Peninsula of Mexico and the mouth of the Orinoco River in Venezuela.^[14] The cultigen was most likely spread by local people to the Caribbean and South America by 2500 BCE.^[15]

I. trifida, a diploid, is the closest wild relative of the sweet potato, which originated with an initial cross between a tetraploid and another diploid parent, followed by a second complete genome duplication event.^[16] The oldest radiocarbon dating remains of the sweet potato known today were discovered in caves from the Chilca Canyon, in the south-central zone of Peru, and yield an age of 8080 ± 170 BC.^[17][18]

Transgenicity

[edit]

The genome of cultivated sweet potatoes contains sequences of DNA from Agrobacterium (sensu lato; specifically, one related to Rhizobium rhizogenes), with genes actively expressed by the plants.^[19] The T-DNA transgenes were not observed in closely related wild relatives of the sweet potato.^[19] Studies indicated that the sweet potato genome evolved over millennia, with eventual domestication of the crop taking advantage of natural genetic modifications.^[19] These observations make sweet potatoes the first known example of a naturally transgenic food crop.^{[19][20][21][22]: 141 [23][24]}

Cultivation

[edit]

See also: Sweet potato storage

Dispersal history

[edit]

Further information: Sweet potato cultivation in Polynesia

Before the arrival of Europeans to the Americas, sweet potato was grown in Polynesia, generally spread by vine cuttings rather than by seeds.^[25] Sweet potato has been radiocarbon-dated in the Cook Islands to 1210–1400 CE.^[26] A common hypothesis is that a vine cutting was brought to central Polynesia by Polynesians who had traveled to South America and back, and spread from there across Polynesia to Easter Island, Hawaii and New Zealand.^[27][28] Genetic similarities have been found between Polynesian peoples and indigenous Americans including the Zenú, a people inhabiting the Pacific coast of present-day Colombia, indicating that Polynesians could have visited South America and taken sweet potatoes prior to European contact.^[29] Dutch linguists and specialists in Amerindian languages Willem Adelaar and Pieter Muysken have suggested that the word for sweet potato is shared by Polynesian languages and languages of South America: Proto-Polynesian *kumala^[30] (compare Rapa Nui kumara, Hawaiian ʻuala, Māori kūmara) may be connected with Quechua and Aymara k’umar ~ k’umara. Adelaar and Muysken assert that the similarity in the word for sweet potato is proof of either incidental contact or sporadic contact between the Central Andes and Polynesia.^[31]

Some researchers, citing divergence time estimates, suggest that sweet potatoes might have been present in Polynesia thousands of years before humans arrived there.^[32][33] However, the present scholarly consensus favours the pre-Columbian contact model.^[34][35]

The sweet potato arrived in Europe with the Columbian exchange. It is recorded, for example, in Elinor Fettiplace’s Receipt Book, compiled in England in 1604.^[36][37]

Sweet potatoes were first introduced to the Philippines during the Spanish colonial period (1521–1898) via the Manila galleons, along with other New World crops.^[38] It was introduced to the Fujian of China in about 1594 from Luzon, in response to a major crop failure. The growing of sweet potatoes was encouraged by the Governor Chin Hsüeh-tseng (Jin Xuezeng).^[39]

Sweet potatoes were also introduced to the Ryukyu Kingdom, present-day Okinawa, Japan, in the early 1600s by the Portuguese.^[40][41][42] Sweet potatoes became a staple in Japan because they were important in preventing famine when rice harvests were poor.^[42][43] Aoki Konyō helped popularize the cultivation of the sweet potato in Japan, and the Tokugawa bakufu sponsored, published, and disseminated a vernacular Japanese translation of his research monograph on sweet potatoes to encourage their growth more broadly.^[44] Sweet potatoes were planted in Shōgun Tokugawa Yoshimune‘s private garden.^[45] It was first introduced to Korea in 1764.^[46] Kang P’il-ri and Yi Kwang-ryŏ embarked on a project to grow sweet potatoes in Seoul in 1766, using the knowledge of Japanese cultivators they learned in Tongnae starting in 1764. The project succeeded for a year but ultimately failed in winter 1767 after Kang’s unexpected death.^[47]

Names

[edit]

See also: List of sweet potato cultivars

Although the soft, orange sweet potato is often called a “yam” in parts of North America, the sweet potato is very distinct from the botanical yam (Dioscorea), which has a cosmopolitan distribution,^[48] and belongs to the monocot family Dioscoreaceae. A different crop plant, the oca (Oxalis tuberosa, a species of wood sorrel), is called a “yam” in many parts of the world.^[49]

Although the sweet potato is not closely related botanically to the common potato, they have a shared etymology. The first Europeans to taste sweet potatoes were members of Christopher Columbus‘s expedition in 1492. Later explorers found many cultivars under an assortment of local names, but the name which stayed was the indigenous Taíno name of batata. The Spanish combined this with the Quechua word for potato, papa, to create the word patata for the common potato.^[50]

Though the sweet potato is also called batata (בטטה‎) in Hebrew, this is not a direct loan of the Taíno word. Rather, the Spanish patata was loaned into Arabic as batata (بطاطا‎), owing to the lack of a /p/ sound in Arabic, while the sweet potato was called batata ḥilwa (بطاطا حلوة‎); literally (‘sweet potato’). The Arabic batata was loaned into Hebrew as designating the sweet potato only, as Hebrew had its own word for the common potato, תפוח אדמה‎ (tapuakh adama, literally ‘earth apple’; compare French pomme de terre).

Some organizations and researchers advocate for the styling of the name as one word—sweetpotato—instead of two, to emphasize the plant’s genetic uniqueness from both common potatoes and yams and to avoid confusion of it being classified as a type of common potato.^[51][52][53] In its current usage in American English, the styling of the name as two words is still preferred.^[54]

In Argentina, Colombia, Venezuela, Puerto Rico, and the Dominican Republic, the sweet potato is called batata. In Brazil, the sweet potato is called batata doce. In Mexico, Bolivia, Peru, Chile, Central America, and the Philippines, the sweet potato is known as camote (alternatively spelled kamote in the Philippines), derived from the Nahuatl word camotli.^[55][56] In Peru and Bolivia, the general word in Quechua for the sweet potato is apichu, but there are variants used such as khumara, kumar (Ayacucho Quechua), and kumara (Bolivian Quechua),^[57] strikingly similar to the Polynesian name kumara and its regional Oceanic cognates (kumala, umala, ʻuala, etc.^[58]), which has led some scholars to suspect an instance of pre-Columbian trans-oceanic contact.^[59] This theory is also supported by genetic evidence.^[60]

In Australia, about 90% of production is devoted to the orange cultivar ‘Beauregard’,^[61] which was originally^[62][63] developed by the Louisiana Agricultural Experiment Station in 1981.^[64]

In New Zealand, the Māori varieties bore elongated tubers with white skin and a whitish flesh,^[65] which points to pre-European cross-Pacific travel.^[66] Known as kumara (from the Māori language kūmara), the most common cultivar now is the red ‘Owairaka’, but orange (‘Beauregard’), gold, purple and other cultivars are also grown.^[67][68]

Habitat

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The plant does not tolerate frost. It grows best at an average temperature of 24 °C (75 °F), with abundant sunshine and warm nights. Annual rainfalls of 750–1,000 mm (30–39 in) are considered most suitable, with a minimum of 500 mm (20 in) in the growing season. The crop is sensitive to drought at the tuber initiation stage 50–60 days after planting, and it is not tolerant to waterlogging, which may cause tuber rots and reduce the growth of storage roots if aeration is poor.^[69]

Depending on the cultivar and conditions, tuberous roots mature in two to nine months. With care, early-maturing cultivars can be grown as an annual summer crop in warm temperate areas, such as the Eastern United States and China. Sweet potatoes rarely flower when the daylight is longer than 11 hours, as is normal outside of the tropics. They are mostly propagated by stem or root cuttings or by adventitious shoots called “slips” that grow out from the tuberous roots during storage. True seeds are used for breeding only.^[9]

They grow well in many farming conditions and have few natural enemies; pesticides are rarely needed. Sweet potatoes are grown on a variety of soils, but well-drained, light- and medium-textured soils with a pH range of 4.5–7.0 are more favorable for the plant.^[4] They can be grown in poor soils with little fertilizer. However, sweet potatoes are very sensitive to aluminium toxicity and will die about six weeks after planting if lime is not applied at planting in this type of soil.^[4] As they are sown by vine cuttings rather than seeds, sweet potatoes are relatively easy to plant. As the rapidly growing vines shade out weeds, little weeding is needed. A commonly used herbicide to rid the soil of any unwelcome plants that may interfere with growth is DCPA, also known as Dacthal. In the tropics, the crop can be maintained in the ground and harvested as needed for market or home consumption. In temperate regions, sweet potatoes are most often grown on larger farms and are harvested before first frosts.^{[citation needed]}

Sweet potatoes are cultivated throughout tropical and warm temperate regions wherever there is sufficient water to support their growth.^[70] Sweet potatoes became common as a food crop in the islands of the Pacific Ocean, South India, Uganda and other African countries.^[71]

A cultivar of the sweet potato called the boniato is grown in the Caribbean; its flesh is cream-colored, unlike the more common orange hue seen in other cultivars. Boniatos are not as sweet and moist as other sweet potatoes, but their consistency and delicate flavor are different from the common orange-colored sweet potato.^{[citation needed]}

Country	Production (millions of tonnes)
China	48.9
Malawi	6.9
Tanzania	4.4
Angola	1.7
Ethiopia	1.6
World	89.5
Source: FAOSTAT of the United Nations[72]

Sweet potatoes have been a part of the diet in the U.S. for most of its history, especially in the Southeast. The average per capita consumption of sweet potatoes in the United States is only about 1.5–2 kg (3.3–4.4 lb) per year, down from 13 kg (29 lb) in 1920. “Orange sweet potatoes (the most common type encountered in the US) received higher appearance liking scores compared with yellow or purple cultivars.”^[73] Purple and yellow sweet potatoes were not as well liked by consumers compared to orange sweet potatoes “possibly because of the familiarity of orange color that is associated with sweet potatoes.”^[73]

In the Southeastern U.S., sweet potatoes are traditionally cured to improve storage, flavor, and nutrition, and to allow wounds on the periderm of the harvested root to heal.^[74] Proper curing requires drying the freshly dug roots on the ground for two to three hours, then storage at 29–32 °C (85–90 °F) with 90 to 95% relative humidity from five to fourteen days. Cured sweet potatoes can keep for thirteen months when stored at 13–15 °C (55–59 °F) with >90% relative humidity. Colder temperatures injure the roots.^[75][76]

Production

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In 2020, global production of sweet potatoes was 89 million tonnes, led by China with 55% of the world total (table). Secondary producers were Malawi, Tanzania, and Nigeria.^[72] It is the fifth most important food crop in developing countries.^[77] Studies are being done to develop a salt tolerant variety to combat the effects of climate change.^[77][78]

Diseases

[edit]

Main article: List of sweet potato diseases

Sweet potato suffers from Sweet potato chlorotic stunt virus (a Crinivirus).^[79] In synergy with other any of a large number of other viruses, Untiveros et al., 2007 finds SPCSV produces an even more severe symptomology.^[79] I. batatas suffers from several Phytophthoras including P. carotovorum, P. odoriferum, and P. wasabiae.^[80]

Uses

[edit]

Nutrition

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Nutritional value per 100 g (3.5 oz)
Energy	378 kJ (90 kcal)
Carbohydrates	20.7 g
Starch	7.05 g
Sugars	6.5 g
Dietary fiber	3.3 g
Fat	0.15 g
Protein	2.0 g
showVitamins and minerals
Other constituents	Quantity
Water	75.8 g
“Sweet potato”. USDA Database. Archived from the original on 3 April 2019. Retrieved 24 March 2021.
†Percentages estimated using US recommendations for adults,[81] except for potassium, which is estimated based on expert recommendation from the National Academies.[82]

Nutritional value per 100 g (3.5 oz)
Energy	359 kJ (86 kcal)
Carbohydrates	20.1 g
Starch	12.7 g
Sugars	4.2 g
Dietary fiber	3 g
Fat	0.1 g
Protein	1.6 g
showVitamins and minerals
Other constituents	Quantity
Water	77.3 g
“Sweet potato, raw”. USDA Database. Archived from the original on 3 April 2019. Retrieved 24 March 2021.
†Percentages estimated using US recommendations for adults,[81] except for potassium, which is estimated based on expert recommendation from the National Academies.[82]

Cooked sweet potato (baked in skin) is 76% water, 21% carbohydrates, 2% protein, and contains negligible fat (table). In a 100 gram reference amount, baked sweet potato provides 90 calories, and rich contents (20% or more of the Daily Value, DV) of vitamin A (120% DV), vitamin C (24% DV), manganese (24% DV), and vitamin B6 (20% DV). It is a moderate source (10–19% DV) of some B vitamins and potassium. Between 50% and 90% of the sugar content is sucrose.^[83] Maltose content is very low, but baking can increase the maltose content from between 10% and 20%.^[83]

Sweet potato cultivars with dark orange flesh have more beta-carotene (converted to a higher vitamin A content once digested) than those with light-colored flesh, and their increased cultivation is being encouraged in Africa where vitamin A deficiency is a serious health problem.^[84] Sweet potato leaves are edible and can be prepared like spinach or turnip greens.^[85]

Comparison to other food staples

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The table below presents the relative performance of sweet potato (in column)^[G] to other staple foods on a dry weight basis to account for their different water contents. While sweet potato provides less edible energy and protein per unit weight than cereals, it has higher nutrient density than cereals.^[86]

According to a study by the United Nations Food and Agriculture Organization, sweet potatoes are the most efficient staple food to grow in terms of farmland, yielding approximately 70,000 kcal per hectare (28,000/acre) / day.^[87]

Staple	Maize (corn)[A]	Rice, white[B]	Wheat[C]	Potatoes[D]	Cassava[E]	Soybeans, green[F]	Sweet potatoes[G]	Yams[Y]	Sorghum[H]	Plantain[Z]	RDA
Water content (%)	10	12	13	79	60	68	77	70	9	65
Raw grams per 100 g dry weight	111	114	115	476	250	313	435	333	110	286
Nutrient
Energy (kJ)	1698	1736	1574	1533	1675	1922	1565	1647	1559	1460	8,368–10,460
Protein (g)	10.4	8.1	14.5	9.5	3.5	40.6	7.0	5.0	12.4	3.7	50
Fat (g)	5.3	0.8	1.8	0.4	0.7	21.6	0.2	0.6	3.6	1.1	44–77
Carbohydrates (g)	82	91	82	81	95	34	87	93	82	91	130
Fiber (g)	8.1	1.5	14.0	10.5	4.5	13.1	13.0	13.7	6.9	6.6	30
Sugar (g)	0.7	0.1	0.5	3.7	4.3	0.0	18.2	1.7	0.0	42.9	minimal
Minerals	[A]	[B]	[C]	[D]	[E]	[F]	[G]	[Y]	[H]	[Z]	RDA
Calcium (mg)	8	32	33	57	40	616	130	57	31	9	1,000
Iron (mg)	3.01	0.91	3.67	3.71	0.68	11.09	2.65	1.80	4.84	1.71	8
Magnesium (mg)	141	28	145	110	53	203	109	70	0	106	400
Phosphorus (mg)	233	131	331	271	68	606	204	183	315	97	700
Potassium (mg)	319	131	417	2005	678	1938	1465	2720	385	1426	4700
Sodium (mg)	39	6	2	29	35	47	239	30	7	11	1,500
Zinc (mg)	2.46	1.24	3.05	1.38	0.85	3.09	1.30	0.80	0.00	0.40	11
Copper (mg)	0.34	0.25	0.49	0.52	0.25	0.41	0.65	0.60	–	0.23	0.9
Manganese (mg)	0.54	1.24	4.59	0.71	0.95	1.72	1.13	1.33	–	–	2.3
Selenium (μg)	17.2	17.2	81.3	1.4	1.8	4.7	2.6	2.3	0.0	4.3	55
Vitamins	[A]	[B]	[C]	[D]	[E]	[F]	[G]	[Y]	[H]	[Z]	RDA
Vitamin C (mg)	0.0	0.0	0.0	93.8	51.5	90.6	10.4	57.0	0.0	52.6	90
Thiamin (B1) (mg)	0.43	0.08	0.34	0.38	0.23	1.38	0.35	0.37	0.26	0.14	1.2
Riboflavin (B2) (mg)	0.22	0.06	0.14	0.14	0.13	0.56	0.26	0.10	0.15	0.14	1.3
Niacin (B3) (mg)	4.03	1.82	6.28	5.00	2.13	5.16	2.43	1.83	3.22	1.97	16
Pantothenic acid (B5) (mg)	0.47	1.15	1.09	1.43	0.28	0.47	3.48	1.03	–	0.74	5
Vitamin B6 (mg)	0.69	0.18	0.34	1.43	0.23	0.22	0.91	0.97	–	0.86	1.3
Folate Total (B9) (μg)	21	9	44	76	68	516	48	77	0	63	400
Vitamin A (IU)	238	0	10	10	33	563	4178	460	0	3220	5000
Vitamin E, alpha-tocopherol (mg)	0.54	0.13	1.16	0.05	0.48	0.00	1.13	1.30	0.00	0.40	15
Vitamin K1 (μg)	0.3	0.1	2.2	9.0	4.8	0.0	7.8	8.7	0.0	2.0	120
Beta-carotene (μg)	108	0	6	5	20	0	36996	277	0	1306	10500
Lutein+zeaxanthin (μg)	1506	0	253	38	0	0	0	0	0	86	6000
Fats	[A]	[B]	[C]	[D]	[E]	[F]	[G]	[Y]	[H]	[Z]	RDA
Saturated fatty acids (g)	0.74	0.20	0.30	0.14	0.18	2.47	0.09	0.13	0.51	0.40	minimal
Monounsaturated fatty acids (g)	1.39	0.24	0.23	0.00	0.20	4.00	0.00	0.03	1.09	0.09	22–55
Polyunsaturated fatty acids (g)	2.40	0.20	0.72	0.19	0.13	10.00	0.04	0.27	1.51	0.20	13–19
	[A]	[B]	[C]	[D]	[E]	[F]	[G]	[Y]	[H]	[Z]	RDA

^A raw yellow dent corn
^B raw unenriched long-grain white rice
^C raw hard red winter wheat
^D raw potato with flesh and skin
^E raw cassava
^F raw green soybeans
^G raw sweet potato
^H raw sorghum
^Y raw yam
^Z raw plantains
^/* unofficial

Culinary

[edit]

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The starchy tuberous roots of the sweet potato are by far the most important product of the plant. In some tropical areas, the tubers are a staple food crop. The tuber is often cooked before consumption as this increases its nutrition and digestibility, although the American colonists in the Southeast ate raw sweet potatoes as a staple food.^[89]

The vines’ tips and young leaves are edible as a green vegetable with a characteristic flavor. Older growths may be used as animal fodder.^[90]

Africa

[edit]

This section should specify the language of its non-English content, using {{langx}}, {{transliteration}} for transliterated languages, and {{IPA}} for phonetic transcriptions, with an appropriate ISO 639 code. Wikipedia’s multilingual support templates may also be used. See why. (July 2023)

Amukeke (sun-dried slices of root) and inginyo (sun-dried crushed root) are a staple food for people in northeastern Uganda.^[90] Amukeke is mainly served for breakfast, eaten with peanut sauce. Inginyo is mixed with cassava flour and tamarind to make atapa. People eat atapa with smoked fish cooked in peanut sauce or with dried cowpea leaves cooked in peanut sauce. Emukaru (earth-baked root) is eaten as a snack anytime and is mostly served with tea or with peanut sauce. Similar uses are also found in South Sudan.

The young leaves and vine tips of sweet potato leaves are widely consumed as a vegetable in West African countries (Guinea, Sierra Leone and Liberia, for example), as well as in northeastern Uganda, East Africa.^[90] According to FAO leaflet No. 13 – 1990, sweet potato leaves and shoots are a good source of vitamins A, C, and B₂ (riboflavin), and according to research done by A. Khachatryan, are an excellent source of lutein.

In Kenya, Rhoda Nungo of the home economics department of the Ministry of Agriculture has written a guide to using sweet potatoes in modern recipes.^[91] This includes uses both in the mashed form and as flour from the dried tubers to replace part of the wheat flour and sugar in baked products such as cakes, chapatis, mandazis, bread, buns and cookies. A nutritious juice drink is made from the orange-fleshed cultivars, and deep-fried snacks are also included.

In Egypt, sweet potato tubers are known as batata (بطاطا‎) and are a common street food in winter, when street vendors with carts fitted with ovens sell them to people passing time by the Nile or the sea.^[92] The cultivars used are an orange-fleshed one as well as a white/cream-fleshed one. They are also baked at home as a snack or dessert, drenched with honey.

In Ethiopia, the commonly found cultivars are black-skinned, cream-fleshed and called bitatis or mitatis. They are cultivated in the eastern and southern lower highlands and harvested during the rainy season (June/July). In recent years,^[when?] better yielding orange-fleshed cultivars were released for cultivation by Haramaya University as a less sugary sweet potato with higher vitamin A content.^[93] Sweet potatoes are widely eaten boiled as a favored snack.

In South Africa, sweet potatoes are often eaten as a side dish such as soetpatats.

Asia

[edit]

Further information: Roasted sweet potato and Sweet potato soup

In East Asia, roasted sweet potatoes are popular street food. In China, sweet potatoes, typically yellow cultivars, are baked in a large iron drum and sold as street food during winter. In Korea, sweet potatoes, known as goguma, are roasted in a drum can, baked in foil or on an open fire, typically during winter. In Japan, a dish similar to the Korean preparation is called yaki-imo (roasted sweet potato), which typically uses either the yellow-fleshed “Japanese sweet potato” or the purple-fleshed “Okinawan sweet potato”, which is known as beni-imo.

Sweet potato soup, served during winter, consists of sweet potato boiled in water with rock sugar and ginger. In Fujian cuisine and Taiwanese cuisine, sweet potato is often cooked with rice to make congee. Steamed and dried sweet potato is a specialty of Liancheng County. Sweet potato greens are a common side dish in Taiwanese cuisine, often boiled or sautéed and served with a garlic and soy sauce mixture, or simply salted before serving. They, as well as dishes featuring the sweet potato root, are commonly found at bento (Pe̍h-ōe-jī: piān-tong) restaurants. In northeastern Chinese cuisine, sweet potatoes are often cut into chunks and fried, before being drenched into a pan of boiling syrup.^[94]

In some regions of India, sweet potato is roasted slowly over kitchen coals at night and eaten with some dressing, while the easier way in the south is simply boiling or pressure cooking before peeling, cubing and seasoning for a vegetable dish as part of the meal. In the Indian state of Tamil Nadu, it is known as sakkara valli kilangu. It is boiled and consumed as evening snack. In some parts of India, fresh sweet potato is chipped, dried and then ground into flour; this is then mixed with wheat flour and baked into chapatti (bread). Between 15 and 20 percent of the sweet potato harvest is converted by some Indian communities into pickles and snack chips. A part of the tuber harvest is used in India as cattle fodder.^[10]

In Pakistan, sweet potato is known as shakarqandi and is cooked as a vegetable dish and also with meat dishes (chicken, mutton or beef). The ash-roasted sweet potatoes are sold as a snack and street food in Pakistani bazaars especially during the winter months.^[95]

In Sri Lanka, it is called bathala, and tubers are used mainly for breakfast (boiled sweet potato is commonly served with sambal or grated coconut) or as a supplementary curry dish for rice.

The tubers of this plant, known as kattala in Dhivehi, have been used in the traditional diet of the Maldives. The leaves were finely chopped and used in dishes such as mas huni.^[96]

In Japan, both sweet potatoes (called satsuma-imo) and true purple yams (called daijo or beni-imo) are grown. Boiling, roasting and steaming are the most common cooking methods. Also, the use in vegetable tempura is common. Daigaku-imo (ja:大学芋) is a baked and caramel-syruped sweet potato dessert. As it is sweet and starchy, it is used in imo-kinton and some other traditional sweets, such as ofukuimo. What is commonly called “sweet potato” (ja:スイートポテト) in Japan is a cake made by baking mashed sweet potatoes. Shōchū, a Japanese spirit normally made from the fermentation of rice, can also be made from sweet potato, in which case it is called imo-jōchū. Imo-gohan, sweet potato cooked with rice, is popular in Guangdong, Taiwan and Japan. It is also served in nimono or nitsuke, boiled and typically flavored with soy sauce, mirin and dashi.

In Korean cuisine, sweet potato starch is used to produce dangmyeon (cellophane noodles). Sweet potatoes are also boiled, steamed, or roasted, and young stems are eaten as namul. Pizza restaurants such as Pizza Hut and Domino’s in Korea are using sweet potatoes as a popular topping. Sweet potatoes are also used in the distillation of a variety of Soju. A popular Korean side dish or snack, goguma-mattang, also known as Korean candied sweet potato, is made by deep-frying sweet potatoes that were cut into big chunks and coating them with caramelized sugar.

In Malaysia and Singapore, sweet potato is often cut into small cubes and cooked with taro and coconut milk (santan) to make a sweet dessert called bubur cha cha. A favorite way of cooking sweet potato is deep-frying slices of sweet potato in batter, served as a tea-time snack. In homes, sweet potatoes are usually boiled. The leaves of sweet potatoes are usually stir-fried with only garlic or with sambal belacan and dried shrimp by Malaysians.

In the Philippines, sweet potatoes (locally known as camote or kamote) are an important food crop in rural areas. They are often a staple among impoverished families in provinces, as they are easier to cultivate and cost less than rice.^[97] The tubers are boiled or baked in coals and may be dipped in sugar or syrup. Young leaves and shoots (locally known as talbos ng kamote or camote tops) are eaten fresh in salads with shrimp paste (bagoong alamang) or fish sauce. They can be cooked in vinegar and soy sauce and served with fried fish (a dish known as adobong talbos ng kamote), or with recipes such as sinigang.^[97] The stew obtained from boiling camote tops is purple-colored, and is often mixed with lemon as juice. Sweet potatoes are also sold as street food in suburban and rural areas. Fried sweet potatoes coated with caramelized sugar and served in skewers (camote cue) or as French fries are popular afternoon snacks.^[98] Sweet potatoes are also used in a variant of halo-halo called ginatan, where they are cooked in coconut milk and sugar and mixed with a variety of rootcrops, sago, jackfruit, and bilu-bilo (glutinous rice balls).^[99] Bread made from sweet potato flour is also gaining popularity. Sweet potato is relatively easy to propagate, and in rural areas can be seen abundantly at canals and dikes. The uncultivated plant is usually fed to pigs.

In Indonesia, sweet potatoes are locally known as ubi jalar (lit: “spreading tuber”) or simply ubi and are frequently fried with batter and served as snacks with spicy condiments, along with other kinds of fritters such as fried bananas, tempeh, tahu, breadfruit, or cassava. In the mountainous regions of West Papua, sweet potatoes are the staple food among the natives there. Using the bakar batu method of cooking, rocks that have been burned in a nearby bonfire are thrown into a pit lined with leaves. Layers of sweet potatoes, an assortment of vegetables, and pork are piled on top of the rocks. The top of the pile then is insulated with more leaves, creating a pressure of heat and steam inside which cooks all food within the pile after several hours.

In Vietnamese cuisine sweet potatoes are known as khoai lang and they are commonly cooked with a sweetener such as corn syrup, honey, sugar, or molasses.^[100]

Young sweet potato leaves are also used as baby food, particularly in Southeast Asia and East Asia.^[101][102] Mashed sweet potato tubers are used similarly throughout the world.^[103]

• Jjin-goguma (steamed sweet potatoes)
• Gungoguma, roasted sweet potatoes
• “Gungoguma drum” for roasting sweet potatoes
• Goguma-mattang (candied sweet potatoes)
• Fried, sweetened sweet potato, India
• Taiwanese pastry
• Imo Jōchū (Japanese spirits made with sweet potato)
• Chinese sweet potato soup, popular during the winter
• Camote tops, a Philippine salad made from young sweet potato leaves (talbos ng kamote)

United States

[edit]

Candied sweet potatoes are a side dish consisting mainly of sweet potatoes prepared with brown sugar, marshmallows, maple syrup, molasses, orange juice, marron glacé, or other sweet ingredients. It is often served in the US on Thanksgiving. Sweet potato casserole is a side dish of mashed sweet potatoes in a casserole dish, topped with a brown sugar and pecan topping.^[104]

The sweet potato became a favorite food item of the French and Spanish settlers, thus beginning a long history of cultivation in Louisiana.^[105] Sweet potatoes are recognized as the state vegetable of Alabama,^[106] Louisiana,^[107] and North Carolina.^[108] Sweet potato pie is also a traditional favorite dish in Southern U.S. cuisine. Another variation on the typical sweet potato pie is the Okinawan sweet potato haupia pie, which is made with purple sweet potatoes.

The fried sweet potatoes tradition dates to the early nineteenth century in the United States.^{[109][better source needed]} Sweet potato fries or chips are a common preparation and are made by julienning and deep-frying sweet potatoes in the fashion of French fried potatoes. Roasting sliced or chopped sweet potatoes lightly coated in animal or vegetable oil at high heat became common in the United States at the start of the 21st century, a dish called “sweet potato fries”. Sweet potato mash is served as a side dish, often at Thanksgiving dinner or with barbecue.

John Buttencourt Avila is called the “father of the sweet potato industry” in North America.^[110][111]

Oceania

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See also: Māori cuisine and Sweet potato cultivation in Polynesia

Māori grew several varieties of small, yellow-skinned, finger-sized kūmara (with names including taputini,^[112] taroamahoe, pehu, hutihuti, and rekamaroa^[113]) that they had brought with them from east Polynesia. Modern trials have shown that these smaller varieties were capable of producing well,^[114] but when American whalers, sealers and trading vessels introduced larger cultivars in the early 19th century, they quickly predominated.^{[115][116][117][118]}

Prior to 2021, archaeologists believed that the sweet potato failed to flourish in New Zealand south of Christchurch due to the colder climate, forcing Māori in those latitudes to become (along with the Moriori of the Chatham Islands) the only Polynesian people who subsisted solely on hunting and gathering. However, a 2021 analysis of material excavated from a site near Dunedin, some 250 km (160 mi) further south, revealed that sweet potatoes were grown and stored there during the 15th century, before the industry was disrupted by factors speculated to be due to the Little Ice Age.^[34]

Māori traditionally cooked kūmara in a hāngī (earth oven). This is still a common practice when there are large gatherings on marae.

In 1947, black rot (Ceratocystis fimbriata) appeared in kūmara around Auckland and increased in severity through the 1950s.^[119] A disease-free strain was developed by Joe and Fay Gock. They gave the strain to the nation, earning them the Bledisloe Cup in 2013.^[120][121]

There are three main cultivars of kūmara sold in New Zealand: ‘Owairaka Red’ (“red”), ‘Toka Toka Gold’ (“gold”), and ‘Beauregard’ (“orange”). The country grows around 24,000 metric tons of kūmara annually,^[122] with nearly all of it (97%) grown in the Northland Region.^[123] Kūmara are widely available throughout New Zealand year-round, where they are a popular alternative to potatoes.^[124]

Kūmara are often included in roast meals, and served with sour cream and sweet chili sauce.^{[citation needed]} They are served alongside such vegetables as potatoes and pumpkin and as such, are generally prepared in a savory manner. They are ubiquitous in supermarkets, roast meal takeaway shops and hāngī.

Among the Urapmin people of Papua New Guinea, taro (known in Urap as ima) and the sweet potato (Urap: wan) are the main sources of sustenance, and in fact the word for ‘food’ in Urap is a compound of these two words.^[125]

Europe

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In the Veneto (northeast Italy), sweet potato is known as patata mericana in the Venetian language (patata americana in Italian, meaning “American potato”), and it is cultivated above all in the southern area of the region;.^[126][127]

In Spain, sweet potato is called boniato. On the evening of All Souls’ Day, in Catalonia (northeastern Spain) it is traditional to serve roasted sweet potato and chestnuts, panellets and sweet wine. The occasion is called La Castanyada.^[128][129] As of 2023 Spain is the largest sweet potato producer in Europe.^[130]

South America

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In Peru, sweet potatoes are called camote and are frequently served alongside ceviche. Sweet potato chips are also a commonly sold snack, be it on the street or in packaged foods.^{[citation needed]}

Dulce de batata is a traditional Argentine, Paraguayan and Uruguayan dessert, which is made of sweet potatoes. It is a sweet jelly, which resembles a marmalade because of its color and sweetness but it has a harder texture, and has to be sliced in thin portions with a knife as if it was a pie.

Globally

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Globally, sweet potatoes are now a staple ingredient of modern sushi cuisine, specifically used in maki rolls. The advent of sweet potato as a sushi ingredient is credited to chef Bun Lai of Miya’s Sushi, who first introduced sweet potato rolls in the 1990s as a plant-based alternative to traditional fish-based sushi rolls.^{[131][132][133]}

Molecular gastronomy

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Freezing a sweet potato until solid, baking at a low temperature, then increasing to a high temperature brings out the sweetness by caramelizing converted sugars.^{[134][135][136][137]}

Ceramics

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Ceramics modeled after sweet potatoes or camotes are often found in the Moche culture.^[138]

Dyes

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In South America, the juice of red sweet potatoes is combined with lime juice to make a dye for cloth. By varying the proportions of the juices, every shade from pink to black can be obtained.^[139] Purple sweet potato color is also used as a natural food coloring.^[140]

Aquariums

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Cuttings of sweet potato vine, either edible or ornamental cultivars, will rapidly form roots in water and will grow in it, indefinitely, in good lighting with a steady supply of nutrients. For this reason, sweet potato vine is ideal for use in home aquariums, trailing out of the water with its roots submerged, as its rapid growth is fueled by toxic ammonia and nitrates, a waste product of aquatic life, which it removes from the water. This improves the living conditions for fish, which also find refuge in the extensive root systems.^{[citation needed]}

Ornamentals

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Ornamental sweet potatoes are popular landscape, container, and bedding plants. Grown as an annual in zones up to USDA hardiness Zone 9, they grow rapidly and spread quickly. Cultivars are available in many colors, such as green, yellow, and purple.^[141] Some ornamental varieties, like ‘Blackie’, flower more than others.^[142] These ornamental cultivars are not poisonous, and although the leaves are edible, the tubers do not have a good taste.^[143][144]